1. Field of the Invention
The present invention generally relates to disk units, and more particularly to a downsized disk unit.
2. Description of the Related Art
A 12 or 18 cm compact disk from which recorded data is reproduced by means of a laser pickup has been employed, for instance, as a storage medium for storing information such as a database or software. Therefore, a disk unit housed in a chassis or housing (a built-in-type CD-ROM drive) has been developed so as to be incorporated into a notebook computer.
A conventional disk unit has its disk tray driven by a motor. When the disk tray moves outside a chassis, a disk is placed on a turntable in the disk tray. Then, the disk tray is moved back again in the chassis by the driving force of the motor.
However, such a tray-driving method employing a motor as the one described above requires a disk unit to include a motor for driving a tray and a transmission mechanism for transmitting a driving force to the tray. This makes it difficult to produce a smaller and thinner disk unit, thus preventing the disk unit from being incorporated into the housing of a notebook computer.
Further, according to the above-described conventional disk unit, a whole disk is positioned in a disk placement portion formed in the disk tray. The disk placement portion is a circular concave portion with a bottom. Therefore, the disk tray is designed to have a width wider than the diameter of the disk. As a result, the conventional disk unit has a wide disk tray and the whole disk unit becomes large in size. Thus, it is difficult to downsize the conventional disk unit.
Therefore, there has been developed a disk unit that dispenses with the above-described motor and transmission mechanism and moves a disk tray, by a manual operation, to a housing position inside a chassis or to an ejection position outside the chassis.
As such a disk unit, the inventors have proposed a disk unit disclosed in Japanese Laid-Open Patent Application No. 11-259947. The disk unit includes a disk tray whose one side portion is cut off so that a disk has a portion protruding therefrom, and a chassis movably holding the disk tray.
Specifically, the chassis holds the disk tray so that the disk tray is movable between an ejection position in which the disk is placed on or removed from the disk tray and a housing position in which the disk tray is housed in the chassis. Further, the chassis includes a housing portion for housing the disk tray when the disk tray is in the housing position. In addition, the chassis includes a cover portion for housing the portion of the disk protruding from the disk tray when the disk tray is in the housing position. This structure allows the width of the disk tray to be decreased and accordingly, allows a space required for a disk tray movement to be reduced. Thereby, the disk unit can be downsized.
As previously described, a disk unit can be downsized by employing a disk tray from which a portion of a disk protrudes when the disk is loaded into the disk unit. However, there is a problem that a noise is generated in the disk unit having the above-described structure when the disk is rotated at a high speed.
This noise is generated by the rotations of the disk in a position where the protruding portion of the disk opposes the cover portion. This is because the surface of the cover portion does not smoothly oppose, or is not curved along, the peripheral edge of the disk so that an air current suddenly changes in the position when the disk is rotated at a high speed.
As previously described, the disk unit is used in a notebook computer or the like, which is used in an office or at home. Therefore, noiselessness becomes an important element.
It is a general object of the present invention to provide a disk unit in which the above-described disadvantage is eliminated.
A more specific object of the present invention is to provide a disk unit with improved noiselessness.
The above objects of the present invention are achieved by a disk unit including a tray having one side portion thereof cut off so that a disk placed on the tray has a portion protruding therefrom; a housing which the tray is inserted into or ejected from, the housing including a first portion for housing the tray and a second portion for covering the protruding portion of the disk; and an air current control member having a curved surface, wherein the air current control member is provided in the second portion of the housing so as to have the curved surface opposing a peripheral edge of the disk moved into the housing.
The above objects of the present invention are also achieved by a disk unit including a tray having one side portion thereof cut off so that a disk placed on the tray has a portion protruding therefrom; a housing which the tray is inserted into or ejected from, the housing including a first portion for housing the tray and a second portion for covering the protruding portion of the disk; and an air current control member provided in the second portion of the housing for controlling a flow of air currents generated by rotations of the disk so as to prevent the flow of the air currents from changing greatly.
According to the above-described disk units, a noise generation is prevented by providing the air current control member in the second portion since this structure prevents the flow of air currents generated by the rotations of the disk from changing greatly.